Merge pull request #3166 from dzhwinter/no_gradient

"add no gradient"

paddle/framework/op_registry.h

@@ -400,6 +400,14 @@ class GradOpRegisterHelper {
     return 0;                                                                  \
   }
 
+/**
+ * Macro to Forbid user register Gradient Operator.
+ */
+#define NO_GRADIENT(__op_type)                          \
+  STATIC_ASSERT_GLOBAL_NAMESPACE(                       \
+      __reg_gradient_op__##__op_type##__op_type##_grad, \
+      "NO_GRADIENT must be in global namespace")
+
 /**
  * Macro to Register OperatorKernel.
  */